Variable-speed transmission



`r`Nov. 28, 1950 c. F. voYTEcH VARIABLE-SPEED TRANSMISSION 2Sheets-Sheet l Filed July 23, 1945 INVENTOR.

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Nov. 28, 1950 c. F. voYTEcH VARIABLE-SPEED TRANSMI$SION 2 Sheets-Sheet 2Filed July 23, 1945 y liv Ok INVENTOR. {w W7@ Patented Nov. Z8, 1950UNITED STATES PATENT OFFICE VARIABLE-SPEED TRANSMISSION Charles F.Voytech, Chicago, Ill.

Application July 23, 1945, Serial No. Y606,529

18 Claims. (Cl. 'i4-752) :pending application, 'Serial No. 506,124,filed October 14, 1943 now Patent No. 2,418,378. In the said priorapplication there is described a fourspeed transmission of the planetarytype which utilizes two simple planetary gear sets interconnected toprovide two input elements, an output element, two releasable reactionelements for forward speeds and 'one releasable yreaction element forreverse drive. An automatic friction clutch and a fluid coupling areused to connect the input elements to the source oi power. Because ofthe drag torque which is produced by a fluid vcoupling when the sourceof :power is rotating at slow speeds, e. g. when the source of power isan internal combustion engine and the engine is idling, and also toprovide a positive neutral, a second clutch is used in series with thefluid coupling, the clutch necessarily being of the friction type so asto be engageable while transmitting torque.

In order to relieve the operator of the physical eiiort required tooperate the clutches, hy-

draulic .power means are used in the aforesaid A prior transmission toactuate the series clutch and centrifugal force is used to operate the.clutch for connecting the other input clutch to the source of power.These various clutches are expensive to make and maintain in workingorder. The iiuid coupling is likewise expensive to make and besides isnot very efficient, particularly under heavy loads.

The principal object of this invention is to simplify the means by whichthe input elements -1 of the aforesaid planetary gearing are connectedto the source of power and thus to `make the transmission cheaper tomanufacture and easier retain the functions of both.

Another object of this invention is to provide ratio changing means ofthe type Vrequiring a relief of torque 'before a change in the conditionof the means can be e'lected, wherein the relief `of torque is effectedinthe means without vreducing the power of the prime mover -connected tothe input elements. Expressed a little diierently, this invention `seeksto provide a means for operating a jaw clutch or the llikein such avmanner that 'the position of `the power control element for 'the primemover fneed not be changed lwhile lthe jaw clutch is being shifted, thussimulating a power shift. When" used in an automobile, the ratiochanging means will operate without .thelnecessity of the operatorremoving his fo'ot from the accelerator lpedal despite the fact that themeans inherently :requires a relief initorque 'before it can operate.

Still another object of 'this invention is to provide ratio changingmeans for the power transmission of an internal combustion engine whichis controllable by the power control elem-ent of the engine underordinary conditions, but which will overrule "the power control elementVwhen the speed of the voutput vshaft exceeds 'the optimum speed vfor:anygiven ratio. Thus when installed in an automobile the driver cancontrol the shift .from one yratio to another by means of theaccelerator pedal and can stay in one ratio beyond the point where theVgovernor' associ- `ated with the ratio changing means would tend toeffect a shift. For example, when the driver iinds himself Vonan upgrade`behind -a slow-moving vehicle and the control means would normally`shiit to the next higher ratio because of the lighter throttle whichratio, however, is not capable of accelerating the vehicle to pass theslow-moving vehicle, the driver can stay in the more desirable lowerratio. If, on the other hand, the driver should forget to shift to thenext higher ratio after passing the slow-moving vehicle and the speed of`his own vehicle Yshould increase beyond the vmaximum permissible forthat ratio, then the shift will be effected automatically without anyconscious effort on the l part of the driver.

`the relative direction of drive of the Vinput and output elements ofthe said devices, with control means for eiecting this -cha-nge in thedrection of drive automatically if the driver should fail to produce thechange by reducing the speed of the vehicle engine.

Another object of this invention is to provide a four-speed transmissionfor an automotive vehicle in which the fourth speed is power shifted,with means for momentarily shifting into this fourth speed to assist ineffecting a shift into one or the other of the intermediate speeds.

A specic object of this transmission is to provide a simple control fortoothed reaction elements such that shifts can be made between forwardand reverse speeds quickly, the control being rugged and fool-proof toavoid a simultaneous shift into two ratios.

These and other objects and features of this invention will becomeapparent from the following description when taken together with theaccompanying drawings in which Fig. 1 is a schematic section taken alongthe axis of a preferred embodiment of this invention;

Fig. 2 is a fragmentary plan view of a portion of the preferredembodiment taken along line 2 2 of Fig. 1;

Fig. 3 is a section taken along line 3 3 of Fig. 2; and

Fig. 4 is a schematic diagram of the controls for the embodiment of Fig.l.

Referring now to the drawings for a detailed description of theinvention and particularly to Fig. l, the preferred embodiment is shownin the form of a transmission for an automobile, the transmission havingan input structure which may be a shaft Ill, and output structure whichmay likewise be a shaft II and an intermediate shaft I2. A hollow shaftI3 surrounds the intermediate shaft I2 and is adapted to be connected atits input end to the drive shaft I by means of a friction clutch I4, theeffectiveness of the connection, however, being controlled by afreewheel clutch l5. Said freewheel clutch I5 is in turn controlled by ashift collar I6 so as to provide a neutral position and a drive ineither direction. The mechanism by which clutch I5 is controlled will bedescribed in detail hereinafter. Intermediate shaft I2 is connected todrive shaft I0 by means including a positive or jaw clutch I7 oneelement of which rotates with the drive shaft.

The drive is transmitted from intermediate shaft I2 and hollow shaft I3to output shaft II by two sets of planetary gearing I8 and I9. Planetarygearing I3 is comprised of a sun gear 20, which may be formed on the endof shaft I3, a plurality of planet pinions 2I mounted on a carrier 22and a ring gear 23, planet pinions 2I meshing with ring gear 23 and sungear 25. Planetary gearing I9 is comprised of a sun gear 24 mounted forrotation with a sleeve 25 loose on driven or output shaft II, aplurality of planet pinions 26 mounted on a carrier 2l and a ring gear28, planet pinions 26 meshing with ring gear 28 and sun gear 2d. Carrier22 is driven directly from intermediate shaft E2 by a connection 23which may be a disc or spider and is directly connected to ring gear 28by a connection 30 and a'drum 3i. Ring gear 23 and carrier 2 areconnected to a spider 32 which in turn is connected directly to outputshaft I I so that ring gear 23, carrier 27 and output shaft II rotate inunison.

The reaction elements by which the different torque and speed ratios areobtained comprise a brake 33 for low and second speeds, a brake 34 forreverse drive, and a brake 35 for fourth speed. Brakes 33 and 34 are ofthe positive toothed type and brake 35 is of the friction type so thatbrakes 33 and 34 can be operated only when there is no torque beingtransmitted through the gearing and brake 35 can be rendered operativeor released even though power is being transmitted through theA gearing.

The details of the various elements mentioned above will now bedescribed. Shaft I3 is formed with .a flange 33 to which is secured adisc 3l' forming part of a flywheel 38. Said flywheel 38 hasincorporated therein a plurality of springs 39 through which the driveis transmitted and which perform the function of absorbing torsionalvibrations which may be generated by the internal combustion engine (notshown) supplying the power to be transformed and transmitted.

Flywheel 38 forms part of clutch I4, the flywheel being provided with afriction face 40 and a spaced pressure plate 4I supported from theflywheel by a stamped cover plate 4'2 secured to the flywheel by bolts43. Said pressure plate 4I is centered relative to the flywheel anddriven from it by a plurality of lugs 45 extending into slots 55 punchedin cover plate 42. A friction surface 46 is machined on the radial faceof pressure plate 4I, said surface 46 being spaced from surface 45 sothat a driven clutch disc 41 may be interposed therebetween. Said disc4'1 may be provided with suitable annular friction facings 48 whichcooperate with the friction surfaces on the flywheel and pressure plateto transmit the drive from the flywheel to driven disc 4l, Clutch I4 isenergized by a plurality of wedge-shaped weights 49 supported by aninturned flange 50 on cover plate 52 and driven from the cover plate bylugs 5I operating in slots 52 in flange 50. A garter spring 53 normallyholds the weights in a retracted position. The outward movement of theweights 49 is trans lated into an axial movement of the pressure plate4I by a pair of cooperating angularly disposed surfaces 54 and 55 formedin the wedges and pressure plate respectively. Thus when the iiywheelAis rotated at a suiciently high speed to overcome the force of spring53, which may be selected to coincide with a speed just above the idlingspeed of the engine, the weights 49 will move outward and through theintermediary of Surfaces 54 and 55 will cause pressure plate 4I to moveaxially to compress disc 4'7 against fiywheel 38 to engage clutch I4.

Disc 41 of clutch I4 is secured to a hub member 56 which in turn issplined to a drum 5l constituting the drivin-g member of freewheelclutch I5. Rigidly secured to the flywheel 38 is a disc 58 which isprovided with an axially extending flange 59 on the end of which areformed teeth 6B. Said teeth 6G constitute the driving member of clutchII. It will be noted that disc 58 is connected in series with vibrationabsorbing springs 39 so that said springs will be effective to preventthe transmission of vibrations to clutch I 'I as Well as to clutches I4and I5.

Referring now to Fig. 3, clutch I5 is comprised of cams 6I and 52machined near the end of hollow shaft I 3 and arranged symmetricallyabout a plurality of grooves or depressions B3 equally spaced about theperiphery of shaft I3. A roller 64 is disposed in each groove andmaintained in proper relation therewith 'by a cage 65. Rollers 64 are ofsuch diameter that when they are positioned in a groove they are out ofcontact with oneness 'the .inner l.cylindrical surfacez of .drum5'1 andthe latter is ineffectual to transmit a drive rtohol- 'dow :shaft 13.When `:cage :i515 iis rotated .clock- `:vviseas :viewed'in Fig. 3so that'the rollers are .in -icontact with :cams tli and .the inner surface .l,:no drive will be :transmitted between drum :51 -and .shaft i3 .unless.shaft :I3 tends to rotate in :the A.direction .of .the .arrow lat ahigher speed Ythan :drum 57i. When .cage 5 is rotated counterclockwiseas viewed in Fig. 3 so that .the rollers ,are in .contact with .cams 62and v theiinn'er survface '66, .no drive will be `transmitted 'between.drum 57i andshaft :i3 unlessshaft is :tends to ire-- .tat-e thedirection .of .the .arrow .at a slower speed thandrum .5.7

The .Control for :cage is comprised .of two or Amore arms Eil (Fig. 1:).extending through arcuate .slots 16B in a ring 59 fsplined to shaft i3and xed :against raXial .movement thereon by asnap ring 'short:angularlydisposed vsection 15 y(Fig. 2), an

.axlial A'section 1? and :a relatively long `ang-ularly Ydisposedsection 11S, ltheslope of t .e 'last-men- -tioned section @bein-gopposite to that of the short .section 115. 'Thus lwhen -pin 5M is atthe end of section .T6 as shown in Fig. '2, cage E55 will posil'tionrollers '64 in the grooves 63 so that no drive will be transmitted ineither direction -of rotation of drum 51 relative to shaft i3. Thisconstitutes the neutral position of -clutch .65. Shifting colla-r Hi tothe left `as viewed Iin Fig. 1 until pin l l is in section 'H willcauseicage 65 to move rollers L64 into .contact with cams therebyestablish- 'ing -a drive 'between drum 5i and shaft i3 when -the -saiddrum tends -to rotate faster than shaft 1113, and continued shift of thecollar it to vthe l'lef-tnntil pin :H reaches the end of section 'i8vwill cause cage t to `move rollers 54 into contact -with 'cams 6I,'thereby establishing a drive between the said drum Aand Yshaft whenthe said drum l-tends to rota-te slower 'than shaft i3. It is understoodthat the shape of the slot sections as well as their length maybemodiiled Yto produce any desiredsequence or rate vof movement of pin 1l.

To avoid an abrupt shift of the rollers 65 into contact with camsurfaces iii a blocking mechav'nisrn is used, This mechanism isIcomprised -of a ring 19 interposed between ring I{il} and drum 51,ysaid ring TS having a lug Si? extending into a slot 8i in a 'flange il?on ring 39 to form a lostmotion connection between rings 'and le. vSaidring 19 has a-conicalAsur-face 83 cooperating with a conical surface '84on the end of drum -'l to provide a friction drive therebetween. Aspring v85 is interposed between flange S vand A:ring .T9 to-cause .thefriction surfaces 83 and 8f4 to contact 4'one another continuously withalight pressure and thereby compel ringr l to bebiased in the ydirectionin which drum 5l is `moving relative to ring- 69. Thus when drum 5itends to -rotate ahead of ring A35 lug Si! will be at 'the lower lend(Fig. 2) of slot 8l and when drum 5l tends to lag behind ring BQ lugiwill be at the upper end lof-theslot.

`Ring 19 is provided with radially extending teeth 8e which extend intothe path of movement'of similar teeth :B7 vformed Vin the end region oflshift-collar I5. If-collar L6 is moved to the left iEig. rh) lwhile lug'.80 lis in the position shown -in Fig. Zteeth will not .bealigned withteeth 8i and zfurther :movement of collar t6 lin .this direction willhbe blocked until drum 51 .tends nto rotate at a;slower .speed 'thanvring 69. r--Ilhe :point at which the movement yof shift collar I6is'bloclzed occurs when .pin v'H .is in the vmddlecf section i of slot:l2 which Acoincides with the neutral lposition of rollers 64, i. e.,when rollers Se `are in the grooves E33. When lug 80 is moved -to :theAopposite end :of lthe slots lill teeth B are aligned .with Ateeth 8lfand shift .collar i8 lcan move eunhindered until .pin 11 reaches :therighthand end (Eig. 2) vof section d8. This eects :a shift of rollers S4into contact with cams 6,1.

- Clutch l'l is .comprised of .a shift-collar lhaving a sliding .splinedconnection 89 with intermediate .shaft t2 and .internal clutch teeth 90at lthe left-.hand end r(Eig. "1) thereof which are adapted :to `meshwith teeth iil on flange 59 to form a driving connection between saidflange :and the .intermediate shaft i2. To avoid tooth .clash .resulting.from an attempted shift .when

vthe flange and shaft are rotating asynchronously a bloching ring 9isimilar to blocking ring i9 lis .interposed .between teeth 95 and 69.Said ring fili `has a lost-motion connection 92 withshaft 12,.a conicalsurfacefcooperating with a conical surface 'Sli on .flange 5S, .andteeth 95 vlocated in the .path .of movement of teeth '90. A spring 96constantly biases .ring -9l toward flange 59 to engage the frictionsurfaces 9S and 94, thereby causing the position of vthe block-ing ring91 to be .controlled by the relative speed of rotation between theflange land .intermediate shaft. The lost-motion vconnection `92 is suchlthat movement of shi-ft collariSB-into clutching position is blockeduntil the relative directionof rotation between :the two elements 4oflthe rclutch changes, i. e..until the two.elements-arezrotating atsubstantially the same :speed and .blocking ring 9i has been rolled outyof the way, thereby avoiding tooth clash.

`tion between the .collar and sleeve.

Shift collar 83 is .controlled from shift collar .I5 by a sleeve 9?Aslidable .axiallyon intermediate shaft l2 and having .a gro-ove 98 inwhich rides one Aor more pins 'til secured to shift collar i5. To allowfor .the .axial movementof shift .collar 16, relative 'to hollow shaftI5, .pin 99 'operates in :a slot il] in said hollow shaft. Theconnectionbetweensleeve 9.1 and shift collarJS is a Spring -lill whichis compressed between the sleeve and collar to transmit the engagingmovement lof l'sleeve 91 .and .a snap ring lii2 which transmits thereturn or disengaging movement. rEhe .dis- .engaging movement is eectedwhen snap ring EQ2 strikes a shoulder tilt formed on the lend of collar.3s during movement of sleeve 91 to the rleft a sufficient distance to.take up the lost mo- Thus a lost- `motion .connection is provided iinthe engaging direction which permits the shift collar It to move to the-limit of its shift while shiftl collar :38 is :waiting to .besynchronized with flange r59, the spring .i 9.! meanwhile storing theshifting energy and 4releasing itfwhen engaging-movement of shift collar88 .can be resumed. For the disengaging .function a positive connectionis used .with :insures disengagement when and as eX- -pected.

Turning now to the various brakes 33, 34 and `35 mentioned `:brieflyabove, Abrake :353 is Acomprised Aof a .wheel its havingteeth |65 on theperiphery clutch |06 is so constructed as to permit gear 24 to rotatefreely when said gear tends to rotate in the same direction as driveshaft I5, but constrains said gear to rotate with wheel It@ when ittends to rotate in the opposite direction. Wheel |04 is held againstrotation by a sprag I0? in the form of a gear sector mounted on an arm I08 secured to a transverse rockshaft |09. When the rockshaft I 59 isturned counterclockwise as viewed in Fig. l sprag I lll is caused toengage teeth of wheel Ill as soon as, or while said Wheel is stationary.Itis contemplated that rockshaft |09 will be manually controlled bysuitable means (not shown) on the exterior of the transmission.

Brake 34 is comprised of an internally toothed Wheel I l5 which rotateswith drum 3| and a sprag III also mounted on arm |08 so that when saidarm is turned clockwise as viewed in Fig. 1 sprag III will engagetoothed wheel II B and hold the Wheel against rotation. It will be notedthat brakes 33 and 311 are mutually exclusive-operable, i. e., wheneverbrake 33 is engaged brake 34 is necessarily disengaged and similarlywhenever brake 34 is engaged brake 33 is necessarily disengaged. Thismutually exclusive operation is essential for the proper operation ofthe transmission as will become apparent from the subsequent*Idescription. It will also be noted that the thrust of toothed wheels m5and I I5 will be taken axially of rock shaft |59.

Brake is fundamentally7 different from brakes 33 and 33 in that it is afriction brake whereas brakes 33 and 34 are of the positive,non-slipping type. can be applied whether or not the rotating member isstationary and irrespective of the tendency of the rotating member tocontinue to rotate due to the continued application of power to it. Saidbrake 35 is comprised of a stationary housing H2 which is secured to thetransmission housing I I3 and is formed with an annular recess ||4 inwhich is located an electromagnet H5. The armature of the electromagnetis a disc H5 se cured at its inner region to a hub III which, in turn,is slidably splined to teeth IIS on hollow shaft I3. Said teeth H8 maybe extensions of the teeth of gear 20. Movement of hub Ill on teeth II8is limited on one side by a snap ring and on the other side by ashoulder I2l formed by the ends of splines '13. A spring I 2lcontinuously urges disc H5 away from electromagnet H5 to avoid creatingunnecessary friction losses, but disc IE5 is nevertheless heldsuiiiciently close to the electromagnet to be attracted .i

thereby when the latter is energized. it will be apparent that brake 35isutilized to arrest the rotation of sun gear 25 or, as will beexplained later, to reduce the speed oi' the sun gear and its associatedhollow shaft I3 to facilitate shifting clutches E5 and Il.

Another brake is provided for sun gear 2li for the purpose of by-passingone-way clutch |06. This brake is shown at |22 and comprises a toothedwheel i 23 mounted for rotation with sleeve 25 and a sprag |213 formedin the end of an arm- |35. Said arm |25 is rotatable with a transverselydisposed rockshaft |25 the movement of which is controlled manually sothat a counterclockwise rotation of the rockshaft causes sprag |24 toengage toothed wheel |23 to arrest the rotation of the sun gear 2dirrespective of the direction of rotation the said sun gear tends toassume. Brake |22 is an emergency brake and is used when it is desiredto use the compression This means that brake 35 of the engine in a lowerratio to hold back the vehicle on a downgrade.

The various ratios available in the transmission so far described arelow, second, direct, overdrive and reverse. A neutral is, of course,likewise available. To. condition the transmission for neutral shiftcollar I 6 is moved to its extreme right-hand (Fig. l) position. Tocondition the transmission for low speed operation brake 33 is renderedelective and hollow shaft I3 is driven through clutches I4 and I5. Forsecond speed brake 33 remains on, clutch II is rendered effective andclutch I5 free-wheels as Well as one-way clutch |06. If, however. it isdesired to circumvent the free wheeling action of clutch |56 as forexample when coasting downhill, brake |22 may be applied and the vehiclewill coast in second speed. The direction of the reaction torque on sungear 24 in second speed is still opposite to the `direction of rotationof drive shaft I so that normally, with power on, brake |22 will beeffective to hold said sun gear stationary. For direct drive, clutch I5is rendered effective to constrain sun gear 20 to rotate at the samespeed as drive shaft I0, clutch I'I remains engaged as well as brake 33and one-way clutch |56 freewheels due to the change in the direction ofthe torque reaction on sun gear 24 which results from the operation ofthe planetary gear sets as locked-up units. Overdrive is obtained fromdirect drive merely by energizing brake 35. Reverse drive is obtained byengaging brake Sil and releasing all other brakes, clutches I and I5being engaged, as for low speed. The power paths through the gearing foreach of the ratios are as follows: For rst speed, from drive shaft I5through friction clutch I4, one-Way clutch l5, hollow shaft I3, gears20, 2|, 23 and spider 32 to driven shaft II, with carrier 22, drum 3i,and gears 28 and 26 reacting against sun gear 21| and transmitting thereaction to spider 32 through carrier 21 and providing a movablereaction for carrier 22. For second speed, from drive shaft I 0 throughywheel 38, disc 58, clutch Il, intermediate shaft I2, connection 29,carrier 22, drum 3|, gears 28 and 26, carrier 2? and spider 32 to drivenShaft II, With gear 2|) of planetary gearset I8 overrunning shaft I2 andgear 24 supplying the reaction for planetary gearset I9. For directdrive both gear sets rotate as units by reason of the fact that sun gear28, and hollow shaft I3 are prevented from rotating ahead ofintermediate shaft I2 and carrier 22 by one-way clutch I5 and hencedrive shaft I5 and driven shaft Il rotate at the same speed. Foroverdrive, from drive shaft Ill, ilywheel 38, disc 58, clutch I1,intermediate shaft I2, connection 29, carrier 22, gears 2l and 23 andspider 32 to driven shaft I I, gear 20 supplying the reaction for planetgears 2|.

The description thus far has been concerned with the power transmittingelements and with the reaction elements and details of the clutches. Thecontrols for these reaction elements and certain of the clutches willnow be described.

It is contemplated that the transmission will be controlledautomatically as a function of both speed and torque, the latter beingrepresented 'by the position of the accelerator or power control lever.To this end a governor |21 is provided, said governor in the form chosenfor illustration being Ior the fly-ball type and comprised of aplurality of balls |28 driven by output shaft II so as to positionthemselves as a function of the speed of the vehicle. The outwardmovementi of the'V` balls is translated into an axial trollever |31'which may be the acceleratorpedal! It will be apparent' that lever' ofthe vehicle. |30 is a floating lever and that the position ofbar |32will' be influenced By the joint action-- of governor |21` and pedal |31so that at times-l movement of the bar |32 will be-dela-yed or re-vtarded by the pedal |31-if said pedal-is depressed more'-v than theusual amount. This means that when the operator of the vehicle wishestoaccelerate the vehicle and' hence desires'to remain in a" lower ratiolonger', the mere depression of' the accelerator pedal in'- the naturalwaywill: automatically override the governorand delay the vmovement ofthe lbar |32 t0 the left as viewed in-Fig. 4, and this in turn, as willbe pointed out below,' will delay shift of the' devices controlled bythebar.

Telescoped inv hollow bar' |32A is a rod? |f38 the opposite end of whichis telescoped in' the hollow portion |39" of another bar |46'. Said bar|46- is pivotally connected' at- |48'to1a lever |6| one end of which isconnected to'- yoke 15 which rides in groove'13'of shift collar |63andthe-other end of whi'chis pivotally connected to one end of al tof,-lg1e"|l|2` serving in this case as an overcent'er device; 'Ifhe otherpart |63" of the toggle |42;4 is' in the'form of a'bell crank anchoredat-|'l|'4 and conne'cted at |45` t'o'a manually operated` lever |46which-is controlled fronlthe operators compartment'. A spring |41 istensionedbetweenthe ends of the 'toggle and maintains the'toggle ini-oneor' thefother of its limiting positions;

andivicelver'sa throughsprin'gs leg-'and |56. The' end |5`| of'springmais anchoredin a' flange |52 and end7V |53 is' anchored inf a flange|56! onrod' |38 Similarly spring' |56 has' one end' |55 anr`getheras-.a'f 1u nit,loutY if' one-bar encounters aresist'ancewhile theother' is' attempting to move'- ita-,springs I'A'S'andL |501 will'compress orexpand' and-will'move flange |54l toward or away? from@ ange|51 or flange |52.

Secured-to flange |51 is a-U-shap'e'd-rod' |58-'onthe'v inside of'whichare electrical contacts |595 and-|66 which are connected togetherby'a' wire I6 |l but are electrically insula'tedfrom rod |58'.A-c'ontact |62' is mounted on flange |54 so as to! be" movable withsaid' flangebetween contacts- |59-'a'nd|66. Thus-when rod |32-i'smovedtoward'- ro'd- |46' and the latter r'e'si'st's,` springs |46 and'-rela'y' |662 andground- |61,v relay |66 havingl a switch |68which-connects wire |61! to electro# magnet |5 and ground |69. It'visapparent' thatA when@ contae't'- |62' str-ikesieither? contacts! |59of a latch' |16; which is'j pivotallyl mounted onrockshaft- |26 androtatable with said rocksha'ft into and out-of? alignm'ent-with-anabutment movable-with-har |3212 Latch-|16-iss'o oriented-on'- rock'shaft|26 that it'will-be in alignment-with ahutment- |1v| when brake |22 isoperated; Shouldy the transmission be inahigher ratio!- than secondspeed'-- at'the' time brake |22 isvto be` operated then' latchv|'16-will serve a's--asafety device-'topr'event ashif-t into-two ratiossimultaneo'usl'y.`

Having? describedthe 'componentsof the-transmission,- the operation of?the' transmission asa whole will not be desc-ribedi Assuming firstthefco'ndition wherein the drive' shaft I-llAk is st'ationary'as well asthe driven shaftl which is the condition which obtains when the'cvehicle engine i's dead` andv the vehicle itiself is standing still,collar |'6willbe in its neutrali position and willbe heldthere by toggle|142. Said toggle will be so positioned' bymovem'en't of` control-lever|46'- tothe right as viewed-in Figi l which causes the toggle to assume"the dotted position shown in that-figure; The'asso'ciated lever Ml willpivot aboutthe'e'ndof bar' |461' sothat the' collar'v |6 will be movedtoVv they right'- (F'ig.l 1)' until the-lef-t-hand-en'd o'f-'lslot' 12contacts'- pin 1|. This positions cage 65'- of clutch I5 so that-therollers- 64 thereofare in' the' depressions 63- andhenee' areineifectualto transi- -mit a drive in' either direction. The'movem'ent'ofr control lever |'46- may he coordinatedl with the' mov'e'nientv ofrockshaft' |69 by any suitable means (not'shown) so that the latter willhold' sprag's |01' and |1|| outl of contact with their respectivetoothed wheels |505 and' |'|6' thereby' preventing the establishment ofthe necessary'reaction'for-a'drive through'the gears infeitherforward'or reverse' directions. The control for second speedlockupclutch|22 however is'independent-of the control-for rod |46 so that ifitis-de'- siredto h'old'thev vehicle' in'gear, as is required b'y law insome states, this can be doneby manually-v rotating rockshaft |26'counterlockwise as viewed.' in Figs. 1 and-4 until sprag |24'contaotswheeli |23; Thef operation of" brake |22 'will cause sun gear 24to be held and will condition the transfmission for secondspeedoperation whether-'the driven'V shaft' or` the drive' shaft' is-thedriver'.`

When it'isdesir'ed to shift the transmission intoA forwardlowspeeddrive, control lever |46 is moved inthe oppositefdirec'tionto`cause tog'- gle" |421' to assume thev solid position' show-n inFig..4 and-rotate lever |41 about pivot |48' until pin' 1|" is 'slid`into straight' portion 11 ofy slot-122 This' rotates cage'65until'rollers 64' are wedged.'v

between-I cams` 62 and' cylindrical surface` 661' and; are'thusrendered'effective'to transmit' a drive from clutch |'4' to hollowshaft I3. Simultaneously with' the movement of control lever! |46"tioned' for' low' spe'edoperation;-

The engine having been started prior-tothe shift to low so that it isnow idling and drive shaft |9 is rotating slowly, the vehicle is startedmoving by depressing the accelerator pedal |31 to open the enginethrottle (not shown) and thus speed up the engine. As the speed of driveshaft ||J increases above the engaging speed of clutch |4 the weights 49will move radially outward thereby moving pressure plate 4| againstclutch disc 41 and compressing the latter against flywheel 33. Thedriving torque is then transmitted through the clutch |4 to clutch I5and the latter having been conditioned to transmit the drive by theshift of collar i9 will turn hollow shaft I3 and its associated sun gear20. With sun gear 24 as the reactance member, the drive will betransmitted to spider 32 and finally to driven shaft I. Said drivenshaft being connected to the drive wheels of the vehicle, the latterwill begin to move and will accelerate. The increased speed of thedriven shaft will cause the balls of the governor |21 to move outward,thereby shifting rod |39 to the left. This will cause bar |32 to move tothe left likewise, the movement being transmitted through the springs|49 and |55 and bar |40 to lever |4I. This in turn will urge shiftcollarI6 to its second speed position wherein positive clutch I1 is engaged.

The leftward movement of bar |32 may be arrested by the depression ofaccelerator pedal |31 to an unusual degree as may occur when it isdesired to reach a high engine speed quickly and it is advantageous toremain in low speed ratio at a higher vehicle speed. This operation ofthe pedal is instinctive and requires no conscious effort on the part ofthe operator. Even With a wide-open throttle, however, a speed willeventually be reached at which clutch I1 will tend to engage, but actualengagement will not occur unless either one of two conditions are setup. Under both conditions it is necessary to reverse the relativedirection of torque between the two elements of clutch l1. Due to thearrangement of the gears, when the transmission is operating in lowratio intermediate shaft I2 is rotating slower than drive shaft I9 andblocker 9| is blocking shift of clutch l1. To unblock clutch |1 underthe first condition the engine is decelerated by releasing theaccelerator pedal |31, thus slowing down sun gear 20. The vehicle,however, continues to move at substantially the same speed andeventually a speed is reached at which drive shaft I Il begins to rotatemore slowly than intermediate shaft |2 at which time blocker 9| willroll out of the way and clutch |1 will be engaged.

Under the second condition, clutch |1 is unblocked without anymanipulation of the accelerator pedal, that is to say, the shift ofclutch |1 is effected in the same manner as a power shift despite thefact that clutch |1 is a blocked positive clutch and hence must besynchronized and then reversed. To effect such shift with manipulationof the accelerator pedal, the operator merely continues to acceleratefor a given accelerator pedal position until the vehicle is moving atthe speed at which no further advantage can be gained in remaining inthe low ratio. At this point governor 21 will have moved lever |30 andits associated bar |32 to the left as viewed in Fig. 4 and sincemovement of bar |39 is arrested by the refusal of clutch I1 to engagedue to the blocked condition of teeth 95, springs |49 and |59 will becompressed, thereby moving rod |38 to the left until contact |62 touchescontact |59.

At this point a circuit will be established from battery |54, conductor|63, contacts |62 and |59 and relay |58, thereby energizing said relayand closing contacts |63. This in turn energizes the electromagnet ||5of friction brake 35. At this point the power will be transmitted fromdrive shaft |9 through clutches I4 and |5 to hollow shaft I3 to whichbrake disc IIB is keyed. Said brake 35 therefore when energized willtend to arrest the rotation of drive shaft l0, and as the speed of saidshaft I0 decreases, precisely the same effect is achieved as though thedriver released accelerator pedal |31 to slow down the engine. Thus apoint will be reached wherein the driving element 59 of clutch I1 willtend to rotate more slowly than intermediate shaft l2, therebyunblocking blocker ring 9| and permitting teeth of clutch |1 to passthrough teeth 95 of the blocker into engagement with driving teeth 6B.Just as soon as engagement of clutch I1 is effected, the resistance tomovement of shift co1- lar I6 is removed and the collar and itsassociated lever 14| and bar |39 will move to the left as viewed in Fig.4, thereby relieving the spring pressure in springs |49 and |59 andallowing contacts |59 and |62 to separate. This will deenergize relay|65 and in turn, through the opening of contacts |68, will deenergizeelectromagnet I5. This instantly releases brake 35 and permits brakedisc |6 to rotate freely. As previously described, engagement of clutch|1 automatically effects the disengagement of overrunning clutch |5 andhence establishes a second speed drive.

Since the shift of shift collar |6 for each speed ratio is progressivein the same direction, the shift from second speed to direct drive maybe effected in the same manner as the shift from first to second. Thus,in shifting from second speed to direct drive, it is necessary to shiftroller cage 65 in the direction to prevent clutch |5 from overrunning.Although clutch l5 is, in a sense, a friction clutch, it is undesirableto engage the clutch until the driving and driven elements thereof aresynchronized. Hence, to shift from second speed to direct drive aftergovernor |21 has positioned shift collar I6 to effect the necessarychange in the position of cage 65, the operator may either release theaccelerator pedal, thus permitting the intermediate shaft |2 to slowdown and with it slow down hollow shaft I3 until the two are rotating atthe same speed as drive shaft |0, whereupon blocker 19 is moved out ofthe way and teeth 31 of shift ring I6 are permitted to pass through theteeth of the blocker, or the operator may continue to depressaccelerator pedal |31 and then the resistance of shift collar I6 tomovement to the left combined with the force developed in governor |21will again close contacts |59 and |62 to energize relay |66 andelectromagnet ||5. The latter mode of operation will result in theslowing down of hollow shaft I3 until its speed is slightly less thanthat of drive shaft whereupon the unblocking takes place as aforesaid.

The shift from direct drive to overdrive is effected by the operation ofgovernor |21, closing contacts |59 and |62 against the resistance ofshift collar |6. It will be observed that after collar IB has beenshifted to the direct drive position, pin 99 will be at the left-handend (Fig. 1) of slot |00 so that above third speed or direct drive,further movement of governor |21'must necessarily compress springs |49and |50, thereby moving vcontact |62l toward contact 52E-calmes@ |59?andy at s ome; predeterminedspeed'Vl contact |6 2Wi.ll touch. Contact.|59 and again effect the energizationgof'relay |66 and electromagnet||5. Indire tiidrive,V overrunning clutch I5 is conditionedygto permitdrive shaft I to rotate ahead ofhollow shaft I3: and hence, .when brake35 is energized; the shift: from direct drive to overdriveswill. beeffected smoothlyA by the simple release.; ofvuoverrunningclutch whenvbrake 35 isasuicientlyenergized to provide the necessary` reactionforfoverdrive operation;

Upon coasting. down from overdrive'to direct' drive, speed; theshiftwill be effected auton-iatically inthe transmission by thedisconnection-.of contacts; |59`v and |62 inV response to the movement;of. governor. |21- from its overdrive positionto its'direct'driveposition. There is no torque load on interengaging elements whichmustber` released:Y at thistime and hence the downshiftfrom overdrive todirect drive is effected' without i any. difliculty.

Thefdownshiftfrom overdrive to direct'drive rnayalso;l be-.effectedwhile governor |21.is in itsoverdrive position. This is accomplished bysimplytramping down on accelerator pedal |31 to.v.-the.limit ofitstraveLnthereby causing bell crank |36;tof..rotate'in.a'counterclockwise position, moving the 1ink.|34 and lever |302 to therightaasviewedz in Fig. .4: This-in turn moves bari` |32;to.the rightand releases the pressure on springs. |431 and |5521 This in turn willeffect aseparationof' contacts..|59 and |621to deenergize relay |66 andelectromagnet H5. Thus, the governor mayk be overruled should conditionsmake it necessary toxincreasef'the.acceleration of the.vehicle.

In the-y downshift from direct drive to second speedrthe operator mayagain release accelerator pedal |31 so as to permit the speed of theengine and'the torque on. drive. shaft Vto decrease` With thel drivingtorque removed from clutches and |5`, the shift' of "shift collar I6 tothe second speed' position is effected without didiculty; However,should the vehicle be. in direct driveLand-'ascending a steep incline:so that the speed of the vehicle gradually decreases to a point Where ashift to second speed would be desirable, the torque load on clutches |1and |5f-is too great topermit collar I6' to be shifted by the forceofthe governor |21 and springs Il!!!l and |50. The release in drivingtorque is effected,.however, by the energization of electromagnet|`|5.-to` energize brakel 35, thereby slowing down brake disc H6 and'its associated hollow-shaft I3 until a relative reversal of direction;of. rotation is effected between-drive shaft I3 and hollow shaft I3. Theenergization of electromagnet ||5 under these conditions is eifectedfbythe-action -ofgovernorV |21 on bar |32 and springs M9 and |50. Sinceshift collar I6'. cannot move to the vright under torque load between=the driving vand driven elements of clutch: |5,it becomes an anchor sothat the relaxation of governor |21" in response to the slowing down. ofthe vehicle, causes springs M3 andV |50 to be-extended. This extensionevene tually'` results inA contact |62 'touching contact loof-whereupona circuit is established from battery |6411' through contacts |32 and|60 to relay-|66.. Said relay. when energized closes contacts.:l |38VKand energizes electromagnet ||5 as aforesaid. The completion of thevdownshit will automatically disconnect contacts. .|62 and |65) torelease. brake 35.

Thus a.: downshift` maybe effected .Without the.

manipulation Yof the'accelera-torn or.` pedal; thereby simulatinga:power shift. If, however, the. gov-'f ernor isfinits third speedfordirect driveposition:

and increased acceleration is desired, the downshift may still beeffected'by-the operator merely by-depressing the -accelerator pedal f|31fto'sub.-

stantially thelimit of its movement in that direction. This willcause-bar |32 to bemoved to the-right as viewed in Fig. flkin-response-to a similar movementfof link |311 and lever |30-,A andsince shift collar IB is anchored by the torque loadas described: above,the same'extensionof springs |43 and |50 takes place which again reinturn'in itsvslowing down operation. effects the releaseof clutch I5.

Since clutch I1 operates to all intents and-purposes likefclutch |5insofar as-release anden'- gagement under torqueare concerned. it willbe.'

apparent that shift from second to first-speedmay-be effected'in exactlythe same manner' as a. shift from direct drive to second speed. and--hence further description thereof can-bedis pensed. with.

It @is apparentA from the foregoingvf description that-the four-speedtransmission illustrated4 in.v Figs. 1` to 4i, inclusive, provides aysimple meansforf effecting shifts automaticallywithout any. action.:

onv the part of the operator, or semi-automatically with someassistance` from the operator at-the operators option. Means areprovided whereby a synchronization of two clutch: parts is brought aboutby an: exterior devicey which is operablev for effecting; twozshifts ofsynchronizable devices 'f and? then is; operablel to effect a thirdshift in which it becomes the shifting deviceitself; I-nil other words,a shift'device for one ratio in` a multi-ratio transmission is utilized'to assist in effecting othershifts inthe transmission so thatconsiderable.y efliciency is achieved. functionis purelythat of asynchronizing device,

it is rnot `necessary-to make it sufficiently strong' towithstand thefull torque of the engine, but only that torque which results from itsoperationas a ratio-establishing mechanism.

It is Ialso apparent that whereasin the average is merely illustrativeof a preferred embodimentl schematically disclosed and that the scope ofthe invention is not to be limited thereto but is to bedetermined: bythe appended claims.

What isi claimed is':-

l; A variable speedl power transmitting device comprising input andoutput structures, constant mesh variable speed gearing adapted toprovide -a' plurality of speed ratios between said input and outputstructures, a plurality of input members-connected to the gearing, anoutput member for the gearing connected to the output structure, aplurality of clutch means for connecting the inputV members to the inputstructure. one of said clutch means being operable upon substantialsynchronization of the driving and driven" parts*thereof,`a pluralityVof reactionmeans associated with the gearing and cooperating withsaidclutch meansy tove'ffect' thel said *changes-fili* Since its assume.

speed ratio through the gearing, control means for the clutch andreaction means and operating the said one clutch means and at least oneof the reaction means in sequence such that the reaction means isoperated momentarily just prior to the operation of said one of theclutch means to cause the driving and driven parts of the said oneclutch means to reach the synchronization required for operation of thesaid one clutch means through the associated constant mesh gearing andthereby eiect changes in speed ratio while torque is being transmittedto the input shaft.

2. A variable speed power transmitting device for transmitting powerfrom an engine to a load, said device comprising an input structureconnected to the engine, an output structure connected to the load,variable speed constant mesh gearing including reaction means connectedto the gearing, said reaction means being operable while subjected totorque to condition the gearing for highest speed operation, meansconnecting the gearing to the output structure, a plurality of inputmembers connected to the gearing, clutch means for connecting the inputmembers to the input structure, means for preventing operation of one ofsaid clutch means except upon reversal of torque through said one clutchmeans, control means for the said one clutch means to condition the saidone clutch means for operation, and means for operating the reactionmeans momentarily while the input structure is receiving power from theengine and said clutch control means is conditioning the said one clutchmeans for operation, the operation oi the reaction means effecting atorque reversal in the clutch means through the gearing and one of theinput members, thereby permitting the said clutch means to operate.

3. A variable speed power transmitting device for transmitting powerfrom an engine to a load, said device comprising an input structureconnected to the engine, an output structure connected to the load,variable speed constant mesh gearing including reaction means connectedto the gearing, said reaction means being operable while subjected totorque to condition the gearing for highest speed operation, meansconnecting the gearing to the output structure, a plurality of inputmembers connected to the gear- I ing, clutch means for connecting theinput members to the input structure, means for preventing operation ofone of said clutch means except upon reversal of torque through said oneclutch means, control means for the said one clutch means to conditionthe said one clutch means for operation, speed responsive means drivenin timed relation with the output structure for operating the clutchcontrol means, and means for operating the reaction means momentarilywhile the input structure is receiving power from the engine and saidclutch control means is conditioning the said one clutch means foroperation, the operation of the reaction means effecting a torquereversal in the clutch means through the gearing and one of the inputmembers, thereby permitting the said clutch means to operate.

4. A variable speed power transmitting device for transmitting powerfroman engine to a load comprising an input structure connected to theengine, an output structure connected to the load, variable speedconstant mesh gearing adapted to provide a plurality of speed ratiosthrough the device, a pair of input members connected to the gearing, atoothed clutch for connecting one of said input members to the inputstructure, a coupling device connected to the input structure andoperable automatically in response to a predetermined speed of rotationof the input structure to eiect a drive through said coupling device,one-way clutch means for connecting the rst-mentioned coupling device tothe other input member, means for rendering said one-way clutch meansinoperative, or for reversing the direction of drive through saidone-way clutch means, an output member for the gearing connected to theoutput structure, control means for the toothed clutch and the means forreversing the direction of drive through the one-way clutch means, andmeans responsive to the speed of the output structure to operate thecontrol means.

5. A variable speed power transmitting device as described in claim 4, afriction brake for the said other input member operable in conjunctionwith the gearing to render effective one of the speed ratios through thegearing, and means for operating the brake momentarily prior torendering effective another of the speed ratios to effect substantialsynchronization of the toothed clutch through the gearing prior to theoperation of the toothed clutch.

6. A variable speed power transmitting device as described in claim 4, afriction brake for the said other input member operable in conjunctionwith the gearing to render eiective one of the speed ratios through thegearing, means for rendering the operation of the one-way clutch meansdependent upon substantial synchronization of the structure and memberto be coupled thereby, and means for operating the brake momentarily toelect said substantial synchronization.

'7, A variable speed power transmitting device for transmitting powerfrom an engine to a load comprising an input structure connected to theengine, an output structure connected to the load, constant mesh gearingadapted to provide a plurality of speed ratios through the gearing, apair of input members connected to the gearing, each when operativeadapted to produce a diierent ratio, a coupling device connected to theinput structure and operable automatically in response to apredetermined speed of rotation of the input structure to provide adrive through said coupling device, a one-way coupling device forconnecting the first-mentioned coupling device to one of the members,said one-way coupling device being controllable to break the drivetherethrough or to provide a one-way drive in either direction, a jawclutch for connecting the second input member to the input structure,reaction means for holding the rst-mentioned input member againstrotation to produce in combination with the gearing one of said ratios,and means for operating the reaction means momentarily prior to theoperation of the cneway device and the jaw clutch to eiect substantialsynchronization of the one-way device and of the parts to be connectedby the jaw clutch.

8. A variable speed power transmitting device comprising first andsecond planetary gear sets each comprising a sun gear, a ring gear,planet pinions meshing with the sun and ring gears and a carrier for thepinions, means connecting the carrier of the rst set with the ring gearof the second set, means connecting the ring gear of the rst set withthe carrier of the second set, means for releasably holding the sun gearoi the secondi set: againstrotation. to. provide a` react-ion for.torque multiplication; input and output structures .for the device,means for transmitting the drive fromthe ring gear or" theflrst set andthe carrier of' the second set to thedriven structure, a' jaw clutch forconnecting the'. carrier of the rst set tothe driving structure,acoupling device connected tothe driving structure and operableinresponse` tofincrease in speed: ofi the driving structure above apredetermined range of speeds and a controllable one-way clutchconnecting the coupling device to thesun gear off the nrst set, saidone-way clutch. being adapted to transmit a. drive selectively inleitherdirection or to prevent the transmission oi drive therethrough.

9..' A. variable speed power transmitting device as described in claim8, means associated with the jawY clutch for preventing operationthereof except upon a relative reversal of drivebetween the. partsthereof, and means associated. with the controllable one-way. clutchfor. preventing operationthereof inone' directionv or" drive eX.- ceptupon arelative reversal of directionl of ro tation between the partsthereof.

1G. A variable speed power transmitting device as described in claim. 8,means associated with the jaw. clutch for. preventing` oper-ationthereof. except upon a. relative reversal of drive between the partsthereof, means associated with the controllable one-way clutch forpreventing operation. thereof inY one direction of drive except upon arelative reversal of direction of rotationbetween the parts-thereof,brake means operable under torque to arrest. the rotationof the sun gearofthe rst set, and means for controlling the operation othe brake meanstooperate said brake meansmomentarily prior to connection ordisconnection oiv either the jaw clutch or. the one-way. clutch toeffect, by means of the gearing connected between the brake and jawclutch and the one-way device a reversal of drive through the jaw clutchand to effect a reversal of direction of rotation through the onewaydevice.

1l. In a power transmitting device comprising an input structure, asource of` power; connected to the input structure, an output structureconnected to a load, constant mesh speed and torque changing gearingconnected in part to the output structure, said gearing having aplurality of input members, clutch means for connecting one of the inputmembers of thegearing to the input structure, means for connectinganother'of the input members to the input structure andl means forpreventing operation of the clutch means except upon substantialsynchronization of the elements thereof; control means for the clutchmeans comprising means for conditioning the clutch means for operationin. response tothe attainment of a predetermined. speed of rotation ofthe output structure, a power control element for the source of power,means operated by the power control element for delaying the operationof the clutch control means, a brake connected to the gearing, powermeans for operating the brake, and means for controlling the brake powermeans, said brake power control means being operated jointly by thepower control element and the speed responsive means and operated afterthe clutch means has been conditioned for operation and upon the outputstructure attaining a predetermined speed higher than the nrst-mentionedspeed, said brake when operative acting through the gearing and the 18means Lconn'ectingfth'eeother input :member to the input structure to.slow.v down. the input structure, thereby effecting substantial;synchronization of the clutch l means. to. permitsaid clutch. meansA tooperate..

12.1 Ina power transmitting; device. comprising an.l inputstructure: a:source of power. connected to the input structure,V an: output.structure. con.- nected toa-load, constant meshxspeed: and torquechanging gearing connected. in part to-.the out.- putvstructure, saidlgearing having aplurality of inputmembers, clutch means-for connectingone oil the input members of. the gearing to the input structure,meansriior connecting another of the input members yto .the .inputstructures and means for. preventing operation ofi the clutch meansexcept upon. substantial, synchronization of. the elementszthereof;control. means for the kclutch means` comprising means for conditioning,the clutch: means-for operation in response. to the attainment of; apredeterminedv speed. of rotation of the output structure, a, power.control element for thelsourcey of;power, meanszoperatedz. by` the powercontrol element for delaying. the opera..- tion. ofi' the clutchcontrola means, a brake connectedi to anr elementof. theA gearing,electromagnetically: controlled; means forv operating. the brake, and. aswitch. forf controlling. theelectrof. magnetic means, said. switchvbeing. operated jointly. by the. power control element and the speed'.responsive means. andclosed; after the clutch means has beenconditionedfor operation and; upon thenoutput. structure attaining. apredetermined. speed; higher than. the. rst-mentioned speed, saidv brakewhen operative. acting through the gearing. and. the means connectingthe' other. input. member to.- the inputstructure to. slowf down. theinput structure, thereby ef'- fectingsubstantial; synchronizationof theclutch meansto, permiti said. clutch means to. operate.

13.. Inf ai power: transmitting device comprising an: input structure,ai sourcev of: power connected tothe inputstructuref, an. outputstructure cone nectedto a load, constant mesh speedand torque changing.gearing connectedlin part tothe out put structure, said gearinghaving apluralityl of input: members, clutchzmeans'for connecting onectlierinputrmembersfofv the gearing to the input structure, meanslfor.lconnecting another of the input members to the input'struct'ure, saidclutch means being releasable only-upon relief of torque between theelementsthereof,v control1means-or the clutclimeans comprising means forconditioning thel clutch means forvdisengagement in response to a dropin speed" of rotation, of the output structure to a predetermined?value, a power control element for the'source ofpower; a brakeconnected-to apart of the-gearing, power means for operating thebrake,and means for controlling the brake power means, said con trolling meansbeingoperated' in response to the speed responsive"means'reachingl aspeed below said predetermined value, said brake when operative actingthrough the gearing and the means connecting the other input member tothe input structure to-slow down the input structure, thereby eiecting amomentary relief of torque through the clutch means t0 permit the clutchmeans to release.

14. In a power transmitting device comprising an input structure, asource of power connected to the input structure, an output structureconnected to a load, constant mesh speed and torque changing gearingconnected in part to the output structure, said gearing having aplurality of input members, clutch means for connecting one of the inputmembers of the gearing to the input structure, means for connectinganother of the input members to the input structure, said clutch meansbeing releasable only upon relief of torque between the elementsthereof, control means for the clutch means comprising means forconditioning the clutch means for disengagement in response to a drop inspeed of rotation of the output structure to a predetermined value, apower control element for the source of power, a brake connected to apart of the gearing, electromagnetic means for operating the brake, anda switch for controlling the electromagnetic means, means for operatingsaid switch by the clutch control means when said clutch control meansreaches a speed below said predetermined value, said brake whenoperative acting through the gearing and through the means forconnecting another of the input members to the input I structure to slowdown the input structure, thereby eiecting a momentary relief of torquethrough the clutch means to permit the clutch means to release.

15. In a power transmitting device as described in claim 12, a secondswitch adapted to energize the electromagnetically controlled means, andmeans for actuating said second switch while the clutch means isoperated and upon the speed responsive means slowing down to a speedbelow `that at which the clutch means is conditioned for operation.

16. In a power transmitting device comprising input and outputstructures, a source of power connected to the input structure, anoutput structure connected to a load, constant mesh speed and torquechanging gearing connected in part to the output structure, clutch meansfor connecting the gearing to the input structure, and a brake for apart of the gearing, control means for the clutch and brake comprising alever for engaging and disengaging the clutch, speed responsive meansfor operating the lever, said speed responsive means including a pair ofbars, resilient means extensible and compressible between the bars totransmit the motion of the speed responsive means to the lever, andmeans energized as a function of the extension or compression of theresilient means to energize the brake, whereby to control the engagementand disengagement of the clutch means and brake by said speed-responsivemeans.

17. In a power transmitting device as described in claim 16, said clutchmeans being releasable only upon relief of drive therethrough, and meansfor preventing engagement of said clutch means except upon substantialsynchronization of the elements thereof, said brake means being operablewhile power is being transmitted to the input structure.

18. In a device for transmitting power from an engine to a load, aninput structure connected to the engine, an output structure connectedto the load, speed and torque changing gearing comprising iirst andsecond planetary gear sets, each set comprising a sun gear, a ring gear,planet gears meshing with the sun and ring gears and a carrier for theplanet gears; a pair of input ele ments, one connected to the sun gearof the first set and the other connected to the carrier of the rst set,means connecting the carrier of the first set with the ring gear of thesecond set, means connecting the ring gear of the first set and thecarrier of the second set with the output structure, automaticallyreleasable brake means for holding the sun gear of the second setagainst rotation in a direction opposite to that of the input structure,a speed responsive coupling device and a controllable one-way clutchconnected in series between the input structure and the iirst-mentionedinput element, said controllable one-way clutch being adaptedselectively to effect a drive in either direction or to break the driveto the said sun gear connected thereto, a jaw clutch for transmittingdrive between the input structure and the second-mentioned inputelement, friction brake means for holding the first-mentioned inputelement against rotation, a common control for the one-way and jawclutches, said control being movable in one direction successively tobreak the drive through both the one-way and jaw clutches, then tocondition the one-way clutch for drive in the same direction as theinput structure, then to engage the jaw clutch and then to condition theone-way clutch for drive in the opposite direction, whereby to eiectchanges in speed from neutral to irst, second and third speeds; andspeed responsive control means driven from the output structure formoving the common control to its said positions and for controlling thefriction brake to effect a fourth speed.

CHARLES F. VOYTECH.

REFERENCES CITED The following references are of record in the rile ofthis patent:

UNITED STATES PATENTS Number Name Date 1,609,782 Small Dec. 7, 19262,103,540 Livermore Dec. 28, 1937 2,171,534 Banker Sept. 5, 19392,259,732 Burtnett Oct. 21, 1941 2,303,975 Banker Dec. l, 1942 2,329,724Maurer Sept. 21, 1943 2,395,459 Carnagua Feb. 26, 1946 FOREIGN PATENTSNumber Country Date 389,207 Germany June 28, 1924 425,870 Great BritainMar. 22, 1935 568,292 France Dec. 19, 1923

